Let $\text{Ind}$ be the D2224: Set of inductive sets.
The set of natural numbers is the D11: Set
\begin{equation}
\mathbb{N}
: = \cap \text{Ind}
\end{equation}
| ▼ | Set of symbols |
| ▼ | Alphabet |
| ▼ | Deduction system |
| ▼ | Theory |
| ▼ | Zermelo-Fraenkel set theory |
| ▼ | Set |
| ▼ | Collection of sets |
| ▼ | Set union |
| ▼ | Successor set |
| ▼ | Inductive set |
| ▼ | Set of inductive sets |